A Uniform Resource Identifier (or URI) is a string of characters used to identify a name or resource. URI is legacy terminology. In most cases, the term URL should be used instead.

There are many classic tech debates, and the question of what to formally call web addresses is one of the most nuanced. The way this normally manifests is someone asks for the “URL” to put into his or her browser, and someone perks up with, "Actually, that’s called a URI, not a URL…"